Color scale and borders in plotSim heatmaps

[pneuvial]

In the heatmaps generated by plotSim the most distant pairs of data points are plotted in white, which can make the heatmap look incomplete. This is only a problem for very small examples, e.g.

set.seed(0xBEEF)
X <- matrix(rnorm(100), 5, 20)
D <- dist(X)
plotSim(D, type = "dissimilarity")

Suggestions

• add a black border to each cell of the heatmap (not sure how to do this using base heatmaps; would be easy with ggplot2)
• change default color scale (heat.colors are not my favorite anyways!)

[tuxette]

second suggestion addressed starting from commit 9383f3ffa0f9175a0a56c1855a5efae6ab8359b1, where heat.colors has been replace by the default palette of ggplot2::scale_fill_gradient (investigate better choices?)